I was told I have low blood pressure. It was 99.? What could cause it and what do I do to maintain a healthy count? I was donating plasma and this was all the information the tech gave me when she refused to take my plasma because my pressure was too low. She did not offer whweter it was the top or bottom number. I am a health nut. I exercise, I eat right, I eat whole fruits, cut down on the breads and sugars. I have a vitamin as supplement regimen that definitely works for me. I cite here all the points you have brought up. I was, though, feeling a little light headed prior to the test. I was donating plasma and this was all the information the tech gave me when she refused to take my plasma because my pressure was too low. She did not offer whether it was the top or bottom number. I am a health nut. I exercise, I eat right, I eat whole fruits, cut down on the breads and sugars. I have a vitamin as supplement regimen that definitely works for me. I cite here all the points you have brought up. I was, though, feeling a little light headed prior to the test and didn t feel the greatest this morning.